Many people sprain an ankle sometime in their lives. Lateral ankle sprains are the most common — that means the injury affects the outside of the ankle away from the other leg. Most of them recover nicely with a little ice, rest, and antiinflammatory medications like ibuprofen. Some need additional conservative care with a brace or support of some kind. A little physical therapy helps regain ankle motion, strength, and proprioception (fine tuning joint awareness).
But in a smaller subset of patients who suffer an acute ankle sprain, the ankle continues to hurt and gives out from underneath them. That instability occurs because one or more of the ligaments holding the joint steady has been torn. This can be very limiting and disabling. When nothing helps and the patient doesn’t get better, the question comes up: does this person need surgery? What would be the benefit?
Of course we know the patient wants a pain free ankle that moves perfectly fine again. Is that what they get? In this report, orthopedic surgeons follow 37 patients who had a severe ankle sprain. They also all had what’s called osteochondral lesion of the talus (OLT). The talus is a bone that sits just above the calcaneus (heel bone).
The term osteochondral tell us that the joint cartilage (chondral) and bone (oste) just underneath the cartilage have been damaged. With some of the more severe osteochondral lesions (OCLs), there is a piece of cartilage with the bone attached that is loose in the joint causing further problems. Anytime there’s a problem inside the joint, it’s referred to as an intraarticular lesion.
The problem with a severe ankle sprain that leads to an osteochondral lesion and joint instability is that these are two separate problems requiring different surgical techniques and different rehab approaches. Can they both be treated at the same time? The patients in this study were operated on in one procedure that had two steps. First, the surgeon used an arthroscope to look inside the joint and find any damage to the joint. Osteochondral lesions were removed and the joint surface was smoothed down.
Once that was taken care of, the surgeon repaired any damage done to the ligaments. If the tissue was too damaged to repair, then a piece of tendon from another muscle was taken and used as a graft to replace the torn ligament. Details of the operative techniques used on the 37 patients were provided. A particular method of repair called the Brostrom procedure was modified slightly and used by the surgeon.
Everyone in the study went through the same rehab program under the supervision of a physical therapist. At first the patients were in a cast to protect the ankle. But once the cast was removed and they were given a splint to wear, then the therapist could start gentle range-of-motion exercises with them. This portion of the rehab program occurred about three weeks after surgery.
Six weeks after surgery, the patients were able to use a removable walker boot and gradually put full weight on that ankle. Pool therapy was used before beginning land exercises and high-impact athletic activities. Most of the patients were able to return to normal activities by the end of four months. Those who had larger osteochondral lesions required additional time (up to six months) of rehab and recovery.
All tests and measures as well as X-rays used to evaluate the results showed good ankle stability in all patients. There were some early signs of ankle arthritis in about one-third of the group. Comparing results for patients with ankle sprain versus those who had both ligament damage and osteochondral lesions (OCLs), results were better when there wasn’t an OCL.
Scores on tests of ankle function were better for patients treated for lateral ankle stability without an OCL. Several different scoring systems were used (e.g., the Martin Score, the SANE scale, the Berndt and Harty Scale). By using more than one test, they were able to make sure the differences weren’t because of the kind of testing that was done and were really from the condition of the ankle.
The significance of this study lies in the treatment of both osteochondral lesions and ankle instability at the same time. For osteochondral lesions, ankle motion is needed right away to help develop smooth healing of the cartilage. But movement too early in the recovery phase could cause the healing ligament to tear.
Instead of waiting six weeks to put weight on the repaired ligament (usual treatment), the authors allowed motion at three weeks. This compromise made it possible to encourage cartilage recovery without endangering the healing ligament.
They were able to compare the results of this group to another group of patients they had treated in a different study. The patients in the previous study had osteochondral lesions without ligament injury. Patients in this current study with osteochondral lesions and ankle instability who had three weeks of immobilization in a cast had the same overall results as those in the other study with only osteochondral damage and no ligament damage.
The authors concluded that it is possible to perform both parts of the necessary surgery (removal and repair of osteochondral lesions as well as ligamentous repair or reconstruction) for chronic lateral ankle stability in one operation. Rehab can be modified to accomodate both types of injuries and their different surgical procedures without affecting the final results.